Artificial Selection Dynamics

Overview

This 50-minute lesson (Lesson 18 of 25) is part of a 6th-grade unit titled Exploring Evolutionary Concepts. Students will explore how humans influence evolution through the process of artificial selection. The lesson aligns specifically with Next Generation Science Standards (NGSS) that complement Common Core literacy standards to support scientific comprehension and reasoning.

---

Learning Objectives

By the end of this lesson, students will be able to:

• Explain how artificial selection differs from natural selection.
• Describe how humans intentionally select for specific traits in plants and animals.
• Analyze examples of artificial selection to identify changes in species traits over generations.
• Engage with scientific texts to gather information on artificial selection, enhancing their informational reading skills.

---

Standards Alignment

Science (Next Generation Science Standards - NGSS)

• MS-LS4-4: Construct an explanation based on evidence that describes how genetic variations of traits in a population increase some individuals’ probability of surviving and reproducing in a specific environment. (Applied to artificial selection context.)
• MS-LS4-6: Use mathematical representations to support explanations of how natural selection leads to evolution of populations.

English Language Arts (Common Core State Standards - CCSS)

• CCSS.ELA-LITERACY.RI.6.1: Cite textual evidence to support analysis of science texts.
• CCSS.ELA-LITERACY.RI.6.3: Describe the relationships between a series of historical events, scientific ideas or concepts, or steps in technical procedures in a text.
• CCSS.ELA-LITERACY.W.6.2: Write informative/explanatory texts, including the conveying of scientific ideas clearly.

---

Materials Needed

• Whiteboard and markers
• Copies of a short, age-appropriate scientific passage on artificial selection (2 pages max)
• Pictures or real-life examples of dogs, crops, or livestock breeds showing traits selected by humans
• Chart paper or poster boards
• Colored markers
• Exit tickets (small slips of paper with prompt questions)

---

Lesson Timeline

1. Introduction (7 minutes)

• Engage: Begin with a question — “Have you ever noticed how different dog breeds can be? Why do you think they look so different even though they are all dogs?”
• Show a quick slideshow or pictures of various dog breeds and crops (corn, apples).
• Briefly define artificial selection as the human-driven process of selecting specific traits over generations. Contrast it with natural selection (students will reflect more on this in prior or future lessons).
• Write the definition on the whiteboard for reference.

---

2. Reading & Evidence Gathering (15 minutes)

• Distribute the short science passage on artificial selection, written with clear scientific vocabulary and real examples (e.g., breeding corn for bigger kernels, dogs for specific personality traits).

• Students read individually or in pairs, highlighting/scribbling answers to two guiding questions printed at the top:

  • What traits have humans selected for and why?
  • How do those traits change over generations?

• Teacher circulates to support vocabulary and comprehension, guiding students to cite evidence from text (aligning to CCSS RI.6.1).

---

3. Group Activity: Trait Selection Chart (15 minutes)

• Divide students into four small groups (4-5 students each).

• Each group receives a set of images or descriptions of a plant or animal with artificially selected traits. For example:

  • Group A: Dog breeds (e.g., retrievers vs. bulldogs)
  • Group B: Corn varieties
  • Group C: Apples and fruit size/color
  • Group D: Livestock traits (sheep wool, cow milk production)

• Task: Create a visual poster/chart illustrating:

  • Which traits were selected?
  • Why might humans want these traits?
  • What effects do these changes have on the species or environment?

• Groups will present their poster with 1-2 minutes each.

---

4. Class Discussion & Wrap-up (8 minutes)

• Discuss as a class: “What do you think are some benefits and challenges of artificial selection?”
• Highlight ethical considerations (animal welfare, biodiversity impacts) briefly—introduce critical thinking.
• Reinforce the idea that artificial selection is evolution influenced by humans’ choices, linking back to the unit’s major themes.

---

5. Exit Ticket (5 minutes)

• Prompt students to write a 2-3 sentence answer to:
  • “Explain artificial selection in your own words and give one example of a trait that humans have selected for.”
• Review exit tickets quickly for understanding and to inform future lessons.

---

Differentiation

• Provide reading supports such as vocabulary glossaries or paired reading for ELLs and struggling readers.
• Challenge advanced students to consider the long-term effects of artificial selection on populations or ecosystems in their exit ticket responses.

---

Assessment

• Informal formative assessment during group presentations and class discussion.
• Exit tickets provide a quick written formative assessment of students’ grasp of the concept and ability to communicate scientific ideas clearly.

---

Extensions (Optional for Homework or Further Study)

• Create a mini-project where students research and present on a domesticated animal or crop of their choice, tracing specific artificial selection traits over history.
• Use simple genetics simulations or Punnett squares to explore inheritance of selected traits (could tie into later lessons).

---

This lesson plan leverages scientific literacy, collaborative learning, and critical thinking, ensuring 6th graders develop concrete understanding of artificial selection in a relatable, engaging way—an important step toward grasping broader evolutionary concepts.